Monoazo dyestuffs



Patented June 28, 1949 UNITED 10F .FI CE 'MONOAZO DYESTUFFS Basil Jason 'Heywood,Blackley, Manchester, England, assignor to Imperial Ghemical Industries Limited, a corporation of Great Britain No Drawing. Application .August 3, 1945, .Serial N 0. 608,844. In Great Britain August 28, 1944 4-Claims. 1 This invention 'relates lto the manufacture of new monoazoldyestufis, and more particularly to such dyestuffs as are eminently suitable for dyeing cellulose acetate'artificialsilk and nylon fibres. According to the present invention new monoazo dyestufis are manufactured by a process comprising coupling diazotise'd 2-cyano-4-nitroanilineor a 6- halogeno derivative thereof with the sulphuric ester of an N hydroxyalkyl N- (phenyL naphthyl, phenoxyor 'naphth'oxy) -alkyl (2, 3, 4 'or5 carbon atoms)--aniline which may carry further substituents subject to its *being capable-of coupling in the para-position to the nitrogen atom.

Examples -'of diazo components which may be employed are 2-cyano-4 nitroaniline. 2-cyano- 6-chloro-4-nitroaniline, and 2-cyano-6-bromo 4-nitroaniline.

Coupling components whichmay be usedfor example in this. invention are the sulphuric esters of the following hydroxy alkylated: anilines:

N- p-hydroxyethyl-N- c phenylethylaniline N c hydroxyethyl-N-p =phenylethyl=m-aminotoluene N 13-hydroxyethylaNap phenylethy1424methoxy- .methy1aniline N .5 hydroxyethyl-N-s-phenylethyl--m-aminoanisole N 5 hydroxyethyl-N-c' phenylethyl-m-acetyl- *aminoaniline N 5 hydroxyethyl N-fi-phenylethyl-m chloraniline N-cehydroxyethyl N-: -phenylpropylaniline N-B-phenylethyl-N-c-hydmxy+nipropylaniline N-B-phenylethyleN-e hydroxy-n-arnylaniline N -fl-hydroxyethyl-N-d-phenylethylaniline 'N'ffi'fhiildIOXNBlJhYl -N,-c' -naphthyl (2) ethyl aniline N-fi-hydroxyethyl-N-fl'-phenoxyethylaniline N-p-hydroxyethyl rN-lpep tclyloxyethylaniline N B hydro yethyl-N-fi'-pqchlorophenoxyethyl aniline N ,[3- hydroxyethyl-N-;3'- (a") -naphthoxyethylaniline N ,c-hydroxyethyl-N-fi-phenoxyethyl-m aminotoluene N e i-hydroxyethyl N-fi-phenoxyethyl-cresidine N ,dhydroxyethyl-N-s'-phenoxyethylFm-chloraniline N B-hydroxyethyl-N-p' phenoxyethyl-o-aminoanisole N c-hydrosyethyl-N 3zphemoxyethyl-meacetylaminoaniline N-B-hydroXyethyl-N-a'-phenoxyethylani1ine N-fi-hydroxyethyl-N-v'phenoxypropy1aniline i2 .N-fi-hydroxwmpropyl. -N-B-phenoxyethylaniline N-w-hydroxym-amyl -N- c phenoxyethyl aniline N B-hydroXyethyl-N -w-.phenoXy-n-. amylaniline The'new dyestuffs in the form of their alkali metalor ammonium salts, are soluble in water and have very good aflin'ity for cellulose acetate artificial silk which they dye from a neutral, slightly acid or slightlyalkaline dyebath in violet and blue shades. The resulting shades possess good fastness properties, are dischargeable and are suitable for printing cellulose acetate artificial silk. .The'new dyestuffs are, moreover, generally suitablefor application to cellulose acetate artificial silk fr0mdilute0r long liquors such as are employed in dyeing withlthe winch.

Themew dyestuffs-are also valuable for the dyeingcof wool, natural silk, tin weighted silk, leather and nylon fibres.

"The new dyestuffs are advantageously applied to the 'colourin'g of synthetic fibres, for example, those composedof or comprising cellulose acetate and/or-nylon, which application constitutes a still {further feature of this invention.

Thednvention is illustrated but not limited by the-following examples in which theparts are by weight:

:E'xample 1 16:3 lpartscof 2-.cyano-4-nitroaniline are diazotised by .the'method described in Example 1 of British specification No. 447,561 and the solution .ofthe ,diazo'compoundis poured onto ice and the product. is added gradually to a cooled and stirred solution i of 37.8 parts of the sodium salt of N -41-phenylethyleN-fi-hydroxyethyl-m-chloroaniline sulphuric ester in 400 parts of Water. When the coupling is complete 40% aqueous sodium hydroxide is added slowly to the mixture theitemperature thereofbeingkept below 10 C., until the coupling medium is just alkaline to litmus. LThermiXtureis then stirred during o-ne houraandtheidyestuff is then filtered off, washed ivvithiadittle waterand dried 21130-40" C. This new dyestuffrforms a black powder which dissolves inrhotmvaterrtoggivea reddish violet solution and ,inasulphuricgacidito give a dull red solution. The dyestufi idyeszcellulose acetate artificial silk and nylon fibre :or :fabric in bright reddish violet shades ,of 'very zgoodrfastnessto light and to \vet treatments when appliedfrom a neutral dyebatn containingsodium chloride or sodium sulphate.

Example 2 16.3 parts of 2-cyano-4-nitroaniline are diazotised by the method described in Example 1 ct 3 British specification No. 447,561 and the solution so-obtained is added to a stirred and cooled solution of 35.7 parts of the sodium salt of N-p-hydroxyethyl-N-,3'-p-tolyloxyethylaniline sulphuric ester in 400 parts of water. When the coupling is complete 40% aqueous sodium hydroxide solution is added slowly to the mixture, the temperature thereof meanwhile being kept below 10 C. by

violet solution and in concentrated sulphuric acid to give a reddish brown solution.

The new dyestuff dyes cellulose acetate artificial silk and nylon fibres and fabrics in reddish blue shades of good fastness to light and wet treatments.

Further examples illustrative of the invention are set forth in tabular form below:

Shade 011 cellu- Example N0. Diazo Component Couplmg component acetate artificial Silk N-5-hydro:cy-ethyl-N-fl'-(1-naphthyl)-ethylaniline sulphuric ester violet.

2-cyano-6-chloro-4-niltroaniline N-fl-hydroxy-ethyl-N-B'-phenoxyethylaniline sulphuric ester N-fl-hydroxyethyl-N-fl-p-chlorophenoxy-ethylaniline sulphuric est N-fl-hydroxyethyl-N-B'-p-phenylethyl-1n-toluidine sulphuric ester.

N-p-hydroxyethyl-N-flphenoxyethylamline sulphuric ester Do.

reddish violet.

Do violet.

external cooling, until the mixture is just alkaline to litmus. It is then further stirred for an hour and the dyestuff is then filtered off and dried at 30,-40 C. The dyestuif forms a greenish black powder which dissolves in hot water to give a reddish violet solution and in sulphuric acid to give a dull crimson solution. It dyes cellulose acetate artificial silk and nylon fibre or fabric in violet shades of very good light fastness when applied from a neutral dyebath containing sodium chloride or sodium sulphate.

Example 3 19.8 parts of 2-cyano-6-chloro-4-nitroaniline are diazotised by addition to a stirred solution of 6.9 parts of sodium nitrite in 160 parts of concentrated sulphuric acid. The solution is stirred for 2 hours and is then poured into a stirred mixture of 400 parts of ice and 200 parts of water. This diazo solution is immediately added to a stirred and cooled solution of 34.3 parts of the sodium salt of N-fl-hydroxyethyl-N-fi-phenylethylaniline sulphuric ester in 400 parts of water. When the addition is complete, N aqueous sodium hydroxide solution is added to the mixture until it is just alkaline to litmus, the temperature being meanwhile kept below 10 C. by external cooling. The mixture is then stirred for one hour and the dyestuff is then filtered off and dried. It forms a dark violet powder which dissolves in water to give a bluish violet solution and in concentrated sulphuric acid to give a reddish brown solution. 7

The new dyestuif dyes cellulose acetate artificial silk and nylon fibres and fabric in bluish violet shades of good fastness to light when applied from a neutral dyebath containing sodium chloride or sodium sulphate.

Example 4 19.8 parts of 2-cyano-6-chloro-4-nitroaniline are diazotised by addition to a solution kept below 5 C. of 6.9 parts of sodium nitrite in 160 parts of concentrated sulphuric acid. The mixture is stirred for 2 hours and is then slowly added to a stirred solution of 35.? parts of the sodium salt of N-fl-hydroxyethyl-N-B'-phenylethyl-m-toluidine sulphuric ester in 400 parts of water kept below 5 C. When this addition is complete, 40% aqueous sodium hydroxide is added'until the mixture is just alkaline to litmus. It is then stirred for 1 hour and the dyestuff is then filtered off and dried at 30-40 C. The dyestuff forms a black powder which dissolves in hot water to give a I claim: 1. A monoazo dyestuff which in the form of its acid is represented by the general formula,

| oH-o-soH ON d1 2 4 a 3. A monazo dyestuff which in the form of its acid is represented by the formula 01 I e-Q 4. A monazo dyestuff which in the form of its acid is represented by the formula t C N zHrO-S 0 H BASIL JASON HEYWOOD.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,117,733 Krzikalla May 1'7, 1938 2,361,618 Felix Oct. 31, 1944 2,384,734 Felix Sept. 11, 1945 FOREIGN PATENTS Number Country Date 648,768 Germany Aug. 11, 1937 

